Agriculture has an industry such as hydroponics, based on growing plants in a nutrient aqueous solution or non-nutrient substrate. Gravel, expanded clay, mineral wool, etc. are used as a solid filler. There is a lot of controversy around this industry about its harm and benefits.
Why hydroponics is harmful and useful
Hydroponics can bring harm and benefit to a person, because it all depends on the fertilizing used for plant growth. First, let's look at the benefits of this method. Plants that feed on a solution of minerals receive the whole complex of trace elements necessary for growth. At the same time, the yield increases, there is no need for constant watering, the plants grow strong, develop well. A big plus of hydroponics is that plants are not susceptible to disease-carrying pests. In fact, hydroponics can be environmentally friendly. For example, some countries practice the preparation of a solution for growing plants from coconut milk. Another plus of hydroponics is the ability to harvest year-round.
If we talk about the dangers of this method, then most of it is created by the person himself. Hydroponics itself is harmless. Dangerous chemicals used by unscrupulous manufacturers. Vegetables saturated with such substances are comparable in danger to nitrates. The chemicals are often used on vegetables for sale. The additives enhance plant growth and yield. However, fruits accumulate heavy metals that enter the human body during a meal.
Despite the resistance of hydroponic plants to pests, they still have to be processed. For commercial purposes, additional spraying with solutions is used to increase yields. In case of ignorance or irresponsibility, poisonous substances can be used together with solutions. Getting into the human body together with the fetus, they are a serious source of disease development.
Hydroponic substrates and water
As a solid soil, hydroponics means the use of special substrates. Different fillers are used for their preparation, which depends on the hydroponic equipment and the type of plants:
- Granite chips or gravel are quite popular for making hydroponic substrate. A big plus is their low cost. However, the main disadvantage is the poor water retention of the stone. A granite or gravel-based substrate is suitable for frequently irrigated hydroponic systems such as drip irrigation.
- Expanded clay good for the substrate due to the fact that its granules give the plants access to a large amount of oxygen. However, expanded clay cannot be used for more than 4 years because of its ability to accumulate microbes that develop in plant waste products. The moisture retention rate of the pellets is low. The substrate requires frequent watering.
- Sphagnum moss is a natural component for the substrate. It provides the plant roots with sufficient oxygen and moisture.The use of moss is justified with a wick irrigation system.
- Coconut substrate more durable than moss and contains many useful trace elements. Ideal for any hydroponic equipment, greenhouses and simple flower pots.
- Mineral wool its structure resembles a coconut substrate, only it does not contain organic nutrients. Mineral wool retains moisture well, plus it is durable. When growing plants on mineral wool, you need to take care of high-quality irrigation of the roots with a nutrient solution.
- Perlite is a granule of volcanic rock. The porous filler is ideal for use with wick irrigation. Sometimes perlite is mixed with vermiculite in equal proportions.
- Vermiculite made from mica. It is an organic substrate with a high moisture retention rate, saturated with micro and macro elements. For hydroponics, vermiculite is considered the ideal choice.
In addition to a solid substrate, plants can be grown in liquid solutions. Naturally, water is used for their preparation:
- The composition of the city water drawn from the tap contains chemicals. They are added to purify the liquid and bring it to drinking standards. The worst tolerance for hydroponics is sodium chloride, which causes toxic plant poisoning. However, chlorine tends to evaporate. Before using city water, it must be defended in an open container for at least 3 days, and then passed through a charcoal filter.
- Well and river water is saturated with bacteria undesirable for plants, causing their disease. When using such a liquid, it must first be disinfected with chlorine, and then purified, as was done with water from the city water supply.
- Rainwater contains many pollutants. The collected liquid, flowing down from metal roofs, gutters and other structures, contains many impurities of zinc and other metals. Plus, rain can be acidic. The quality of such water can be judged only after receiving the results of laboratory tests.
- Distilled water is the purest and best hydroponic liquid. The only drawback is the lack of useful trace elements. This issue is solved by adding a higher concentration of nutrients.
With your hydroponic substrates and water sorted out, it's time to familiarize yourself with what kind of setup they're using.
The hydroponic equipment used will influence the choice of the type of substrate, as well as the method of growing plants in water. There are several types of installations:
- Wick installation involves the use of a container with a nutrient solution. A tray with plants growing in the substrate is placed on top of it. Wicks are lowered from the tray into the container, through which moisture enters the substrate to the plant roots. The equipment is suitable for a small garden or exotic plants. This installation is not suitable for growing greens and vegetables.
- Installation from a floating platform more suitable for growing indoor moisture-loving flowers. The equipment consists of a container with a nutrient solution, on which a platform with holes, for example, made of foam, floats on top. Plants grow in these holes. The solution is sprayed to the plant roots under the platform with air compressors.
- Two containers installed one above the other are used as equipment for intermittent flooding.... The lower reservoir contains the nutrient solution, and the upper tray contains the substrate with the plants. A pump, regulated by a timer, pumps liquid into the upper tray, after which it randomly flows back into the lower reservoir. The installation is suitable for a garden or greenhouse.
- Drip irrigation consists of thin hoses connected to the roots of each plant growing on a hard substrate. Hoses supply the nutrient solution to the roots of each plant.The equipment is used in home and industrial growing of vegetables.
- Equipment for aerial cultivation involves the use of an empty, without substrate, containers made of opaque plastic... Plants are simply placed inside a tank and the roots are sprayed with the nutrient solution with an ultrasonic spray. The installation is ideal for a home garden.
A general understanding of the equipment and its operation should be clear to everyone. Now let's look at an example of growing a tomato.
Growing a tomato hydroponically
Growing tomatoes in hydroponics will give good results only with the use of certain varieties, for example, "Gavroche", "Alaska", "Druzhok", "Bon appetite".
The video tells about tomatoes for hydroponics:
The method of making a plant and growing tomato seedlings involves the following steps:
- Mineral wool is impregnated with a solution of water with slaked lime. This achieves an acidic environment for the plant. Tomato seeds are placed in a cotton wool saturated with moisture, after which they are laid out in plastic containers, where the seedlings will grow. The bottom of the container must be drilled with 5 small holes.
- The germinated sprout needs to be provided with a 12-hour supply of light for its development. Slightly matured plants are transplanted in large containers with a disinfected substrate. You can transplant with cotton wool so as not to injure the root system. A drip irrigation hose is supplied to each plant. During the germination of seeds in the mineral wool, light should not be allowed to enter the root system. This is destructive for the plant.
The video tells about tomatoes for hydroponics:
- An adult plant needs up to 4 liters of solution per day. As it grows into the water, the addition of fertilizers is gradually increased, first 1 and then 2 times a week. After the beginning of flowering, for the formation of the ovary, artificial pollination is done with a watercolor brush.
During long-term cultivation, salt accumulates on the root of the plant. To remove accumulations, the tomato is taken out of the container along with the substrate and the roots are washed with clean water.
The video tells about the self-production of hydroponics:
In fact, hydroponics is a profitable and environmentally friendly method of growing crops at home and on an industrial scale. The main thing is to use safe solutions that do not harm the human body.